The earth is in great danger now.We have to do something _______ it.（ ）
A．protectB．protectingC．to protectD．protected
"Pingtang Bridge has the highest concrete bridge tower in the world．""______amazing it is!"（ ）
| A． |
How |
B． |
What |
C． |
What an |
As we all know， using public chopsticks______necessary when we eat with others．（ ）
| A． |
is |
B． |
are |
C． |
was |
After﹣school activities help students gain more skills and teach_____to care about others．（ ）
| A． |
me |
B． |
you |
C． |
them |
"Krystal， do you know how tea is produced？"
"Yes． When tea leaves are ready， they are picked by hand and then_____for processing．"（ ）
| A． |
send |
B． |
are sent |
C． |
were sent |
In difficult times， there are always national heroes_____step up and bring people hope．（ ）
| A． |
whom |
B． |
which |
C． |
who |